


Sometimes You Just Know

by SciFiSlashFreak



Series: Team Save The World [1]
Category: Buffy the Vampire Slayer, Shadowhunter Chronicles - Cassandra Clare, Shadowhunters (TV)
Genre: Alternate Universe - Buffy The Vampire Slayer Fusion, Alternate Universe - Fusion, But tbh Magnus has more important shit to deal with, F/F, F/M, In which i shamelessly fullfill my wish for simon and magnus to be besties, Like as much as this is a malec story a lot of it is focused on simon and magnus friendship, Like very very vague, M/M, Mutual Pining, Pining, Repressed Alec is repressed, Sibling Bonding, the magic of friendship, vague mentions of violence
Language: English
Status: Completed
Published: 2016-08-07
Updated: 2016-08-07
Packaged: 2018-07-29 21:09:10
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,372
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7699438
Author URL: https://archiveofourown.org/users/SciFiSlashFreak/pseuds/SciFiSlashFreak
Summary: <blockquote class="userstuff">
              <p>Magnus has always had a way of just inherently knowing things.</p><p>Which should be great. But now he's been dragged into a world of demons, Slayers and who knows what else. His priorities shift from passing high school to getting him and his friends through it alive.</p><p>And none of this is made any easier when coupled with trying to understand the hot and cold shadowhunter he can't get out of his head.</p>
            </blockquote>





	Sometimes You Just Know

**Author's Note:**

> This started off as a little snippet (Dream a Little Dream) and has now turned into this huge verse I have multiple stories planned for.
> 
> For those who read Dream A Little Dream first you can tell rather quickly this story I set waaaay before that one. No worries though reading that first spoils very little of the story (mostly just a bit of Raphael's plot line. )

Magnus had always known things.

  
When he met Simon Lewis he knew he had met the person he could always count on when he offered Magnus his yellow crayon with a bright smile missing three teeth and then proclaimed them best friends. He had been right, Simon had been a constant from that day forward.

  
When he met Clary Fray he knew the girl would bring plenty of excitement to his life and was had almost thought he was wrong until they were 16, even more excitement than he’d bargained for.

  
He’d known he was different, that he wasn’t whole yet, something was always tingling under the skin. And he was proven right when he had blasted a vampire back through a wall for hurting Simon.

  
And then…. Then there came Alexander.  
.  
.  
.  
He didn’t know what Clary was the first time he met Alec “And **who** is _that_?” Magnus asked, interest clear in his voice as he looked the serious looking brunet who seemed to be waiting impatiently by Clary’s locker. “Did you go get a boyfriend and not tell me? I’m hurt.”

  
“Oh that’s uh Alec. He’s new and I’m just showing him around not-“ a loud clear of the throat and the newly named ‘Alec’ giving Clary an expectant look “I have to go. I’ll see you later.”

  
Magnus didn’t know what it was but it was like something in him unlocked and just like always somehow he just knew that the Raven haired boy with the scowl wasn’t leaving his life anytime soon.  
.  
.  
.  
“Demons? That was a-I’m sorry can we go back to who the hell _you_ are?” Simon demanded of the blonde neither he or Magnus had seen before “Clary have you joined a cult? Is there a meth problem we need to deal with or-“

  
“It literally never stops talking, “ Alec muttered under his breath “Tell me how exactly would you explain what just happened,” he gestured around the now destroyed library, how a study session had turned into a fight for their lives was beyond Magnus.

  
“Clearly I’m on meth too,” Simon said and Magnus couldn’t help but snort in laughter “Because that thing with the mouth tentacles? Things like that aren’t real!”

  
“Simon, maybe we should let the man explain instead of accusing him of being a dealer,” Magnus finally spoke “Besides if anyone is it’s the blonde, Alexander is far too pretty,” that got a wide eyed look and a stuttering start to a very long explanation.  
.  
.  
.  
“You’ve been avoiding the world again,” Magnus said as he had finally cornered Alec in the library their little gang of misfits saved the world from. It was nearly a year now since he and Simon had been let in on the secret. Clary, the one Slayer, Alexander her watcher, her protector. It didn’t take a genius to figure out what Alec was beating himself up over.

  
“She’s safe. She died but she came back…. She’s stubborn like that you know,” he said. The Shadowhunter said nothing as he put the book away a little too violently. “Alexander you didn’t fail her. You didn’t fail any of us.”

  
“I sent her to die!” Alec said through gritted teeth “I sent her to die. I couldn’t do anything except watch as she- We knew going in and… I let her. Because the rules… the rules say-“ he struggled to calm himself, Magnus knew very well what the rules said, Alexander spouted them often enough. But he also knew had Simon not been as stubborn as he was Clary wouldn’t have come back to save the day. And what then?

  
“Maybe it’s time to start doing things your own way. Stop listening to your brain and think with that big heart you don’t want anyone to know you have,” Magnus suggested softly.

  
Alec looked at him like he had just discovered some new otherworldly thing and before Magnus had even noticed the space between them had been closed Alexander’s lips were on his, desperate and searching. Once fully realizing what was happening Magnus was eagerly responding.

  
As if burned by the reciprocation Alec jerked back “I- I shouldn’t have…. I should go.”  
.  
.  
.  
Magnus didn’t really have time to worry about the kiss. What with his sudden ability to see through glamours, that itch under his skin getting worse every day and the presence of a new Big Bad (as Simon referred to them) in the form of a psychotic vampire name Camille who had Simon kidnapped and dangled off a bridge only a week after the 'incident' in the library.

  
Clary was freaking out, of course she was, and Magnus was doing his best to be her rock, her source of comfort. But the itch under his skin grew as his worry did. He’d known Simon even longer than Clary. He was Magnus’ first friend. He’d been through everything with Simon. Simon had almost exclusively stayed at his house during the months where Ragnor, his foster father at the time, was going through the adoption process, Magnus terrified something would go wrong and he’d be shipped off, away from the best parent he’d ever had, away from his only friend. And Simon had simply shown up, sleeping bag and Captain America duffle bag and slept over nearly every night until the adoption was finalized. Simon was the first person he’d come out too as Bisexual and he had smiled and embraced him making Magnus feel like an idiot for ever being nervous. Simon was **HIS** rock. Yes they’d gotten Clary at 13 and Magnus could not imagine life without her, but life without his best friend? Unthinkable in ways he couldn’t explain.

  
“They won’t hurt him,” a voice came from behind him, making Magnus jump as he turned around to see Alec awkwardly standing in the doorway of the library “They need leverage over Clary. The mundane-“

  
“Has a name. How about we use it?” Magnus snapped, he’d heard this from Jace already. But all the words in the world wouldn’t make a difference they could _say_ Simon was safe all they wanted but until he was back cracking lame jokes with him Magnus didn’t have time for empty promises for his safety.  
Alec looked down, he looked slightly taken aback but he didn’t apologize, maybe because they both knew he wouldn’t mean it.

The Shadowhunter was hardly Simons biggest fan but on the other hand Magnus knew Alec wouldn’t let Simon die, personal feelings or not Simon was a part of the weird little Scooby Gang they’d created. A family of sorts, they’d been through hell together and Alec didn’t take that lightly.

  
So it was Magnus who ended up opening his mouth and saying “I’m sorry… I know you’re just trying to help Alexander.”

  
Hesitant Alec stepped forward and gave Magnus’ hand a reassuring squeeze, they sat like that in silence until Clary rushed in saying they had a plan.  
.  
.  
.  
“What the hell was that?!” Magnus said looking at his hands, it was a madhouse. Vampires attacking from all sides, Jace covering the front, Clary the back and Alexander covering from above while he stuck close to Simon. A vamp had broken through and tried to snatch Simon from him. The itch under his skin became a burn and in a blink the vampire was flying halfway across the room and through a wall.

  
Clary was looking at him in shock “Magnus what-“

  
“ENOUGH!” A voice echoed through the halls, a blur of movement and then there Simon was, taken from him once again by the same vampire who had dangled him off a bridge, having used their distraction to his advantage. And he had a knife to Simons throat . “Retreat,” he said to the swarm of undead. There was a beat of silence before the room was clear in half a second.

  
“Look if this is about the jacket then I was totally serious when I said I’d pay for a new one and-“

  
“Dios _shut up_ ,” the vampire said with a look that, under different circumstances would have Magnus smiling. Figures Simon couldn’t stop talking even with his life on the line. “Now you four. Move.”

  
Jace looked like he wanted to protest but all three of the others glared and they ended up following the man to an exit on the roof. With Simon babbling thanks that was easily dismissed with cruel words.

  
It didn’t matter though because Simon was safe. They were safe in the sun. Jace and Alexander away muttering to each other as Clary held on to Simon saying how happy she was she hadn’t lost him, that she loved and needed him , not seeing the slight heartbreak on Simons face that Magnus saw far too often for his liking.

  
That night it was no surprise when Simon showed up at his door with a sleeping bag and his Captain America duffle bag “So….. since when do your hands glow blue?” he asked causing Magnus to bring the other into a hug as he let Simon crumble in on him and cry- He never did get the details of what had been done to his friend but he knew in his way like he always did. Knew that a debt was owed to the vampire who had saved Simon and Camille needed to pay.  
.  
.  
.  
“You know I can’t figure out why you won’t look at me,” Magnus said to Alexander half a month after getting Simon back. In that time he’d been working on controlling his magic. Because that’s what it was. What it had always been. The way he had always just known things. The constant itch under his skin.

  
Most of his time was spent with Ragnor, who had apparently been waiting for his powers to manifest. Had felt them the day they’d met, and now he was teaching Magnus control. Between his lessons and dealing with Camille there was just enough time to be able to pass his classes. But of course time that should be spent studying was being used most of the time wondering about the very question he had just asked.

  
“I can’t figure out if it’s the kiss that’s got you walking around me on eggshells or the fact of what I am?” he mused to himself out loud after Alec didn’t so much as glance up from his book at him, though he had tensed so he was definitely listening, so he continued. “Or is it a combination? Is the kissing me made worse by the fact that I’m a _downworlder_?” he said the word like it was poison on his tongue “I mean hell the name alone shows what you must think of me now. So kissing me must seem like the most disgusting-“

There was a loud noise of the thick book slamming shut, Magnus had finally succeeded in getting a reaction like he wanted and Alec was in front of him “I don’t-“ but he never got to finish because the library doors opened, Alec once again creating distance between them quickly. And Magnus turned to scold whichever of the group had interrupted this break through but instead of Jace, Clary or Simon there stood a gorgeous Raven haired woman, a blonde woman hovering behind her.

  
“Izzy?” Alec sounded shocked even as he moved forward to hug the woman tightly “Who’s she?”

  
The woman smiled brightly hugging Alec back “We have a lot to talk about Big Brother. Meet Lydia…. My Slayer.”  
.  
.  
.  
”So basically what I’m hearing is ‘One Girl in all the world’ is just a line Jace uses to pick up chicks,” Simon said dryly after a long, confusing introduction.

  
“I’m not above slapping you Mundane,” Jace said, no heat behind it. Really by now their arguing had gone from antagonistic to old married couple bickering, it was more amusing than anything else to Magnus at this point.

  
Isabelle for her part was smiling at Simon “While that does sound like a very Jace line this has never happened before. Two slayers alive at once is unheard of. We have no idea what to make of it in Idris. We were hoping you-“

  
“I died,” Clary said quietly, voice shaking. Confirming Magnus’ suspicions that Clary was nowhere close to okay with that experience as she’d been acting. Dying had a way of sticking with you he supposed. “If Simon hadn’t- I almost didn’t come back... But I was dead. And Alec…. He said when one dies another takes her place. So… when I-“ her voice hitched slightly, Jace wrapping an arm around Clary’s shoulder, Simon looking down at his hands, with a grim sort of resignation on his face.

  
“When you died my abilities activated,” Lydia finished quietly, she’d been quiet most of the meeting. “I didn’t know what was going on it was like-“

  
“A rocket going off inside of you,” Clary said finished “Amazing and agonizing at the same time…. I remember.”

  
A small smile of understanding was shared between the two slayers before Lydia turned her smile on Izzy, less respect and more adoration in it “And then Izzy was there and helped me cope. I’d be dead I’d it wasn’t for her.”

  
Isabelle took Lydia’s hand as a show of comfort, ignoring Alec’s shocked look “Now that we’ve cleared up the how…. Let’s solve this vampire infestation you seem to have.”  
.  
.  
.  
They didn’t exactly solve it but two slayers most definitely made a difference in some of the fights, ones where one or more of them should have been dead where handled quickly. Clary and Lydia bonding in a way that only they could have made them fighting together a sight to behold. It was like watching Jace and Alec fight almost but _more_ in a way Magnus couldn't describe.

  
Izzy and Simon bonded as well, the female Lightwood was as much brains as beauty and she helped Simon go over tons of books, helping translate and teaching him to be able to do so in the future without her help. Magnus was almost worried his friend was on the path to another hopeless crush. Not that Magnus didn’t think Isabelle would be lucky to have Simon and they were cute together but you’d have to be blind not to notice the looks between her and Lydia. Luckily Simon wasn’t blind (except when it came to a certain red head) and seemed to keep his puppy dog crush as just that.

  
Alec seemed a combination of elated and concerned at his sister presence, he obviously adored his family but he kept shooting his sister looks that he couldn’t decipher. Not to mention his mission to avoid Magnus had gone into high gear, ensuring they were never alone in a room together.

  
Magnus had almost given up hope, he unlike Simon, could take a hint. He knew when it was time to try and move on. He was in the back on the library when he heard it.

  
“It’s against the rules Izzy,” Alec said, his voice causing Magnus to move further back, unable to resist listening in “You know what the Clave will do if-“

  
“What? Lydia isn’t exactly expendable Alec even with Clary in the picture,” Izzy coubtered, sounding so exasperated Magnus had to wonder how long this conversation had been going on.

  
“But you are,” and wow Alexander really knew how to be blunt didn’t he. “You could be reassigned. You could have your runes stripped and-“

  
“And how is what I’m doing any worse than you Alec? A mundane knowing everything? A downworlder helping? A wanted Shadowhunter that you’re not turning in-“

  
“As if you could ever turn Jace in,” Alec interjected as Magnus tried to figure out what the blonde could have done to be wanted by the Clave and if Clary knew? If so why would she keep them in the dark?

  
“Of course I couldn’t,” Izzy said with a sigh “No more than I could stop myself from feeling how I do,” she hesitated “No more than you can help who you are.”

  
Magnus spent far too much time watching Alec because even though he could only hear the siblings he just knew Alec had tensed up and that sour look was on his face, could practically visualize it. “I don’t-“

  
“It’s just us Alec. You’ve never had to pretend with me,” a small shuffle of noise and silence, Magnus assumed they were hugging “I love you Alec… but you need to learn that the rules don’t need to dictate your life.”

  
Silence and then

  
“I’ll…. Keep that in mind.”  
.  
.  
.  
They had to leave, two slayers in the same place was helpful but hardly effective when you took into account the other hell mouths not being guarded.

  
So when it came time for the final battle between Camille… well Magnus was wishing they could have stayed just a week longer, which explained why he was making light of the situation. It wouldn’t do for the others to see how nervous he was.

  
“I just don’t get why the bad guys are such clichés,” Magnus said as he, Clary, Jace and Alec prepared what would be needed, the itch under his skin was more of a warm glow now. Reassuring. He could finally handle his own. “I mean an abandoned hotel as a lair? The only thing worse would be a warehouse or the sewers.”

  
“But isn’t a library as a base just as cliché when it come to good guy bases?” Clary pointed out, Alec giving a rare smile as Magnus gave an offended gasp.

  
“How dare you. If Simon were here he’d agree with me.”

  
“Where the hell is the mundane?” Jace asked, going for annoyed but a hint of worry slipped past.

  
“Uh here,” Simon popped his head in “And I have a reason for being late so… Don’t be mad maybe?” before anyone could ask why they’d be mad Simon was stepping in, Camille second who had led him to safety following behind them.  
.  
.  
.  
Turns out his name was Raphael (and he did not appreciate ninja turtle jokes) and not every vampire wanted chaos on the streets and an eventual end to the world as they knew it. That and he rather not see his family killed because they were led by a psychotic bitch (not his exact words but Magnus could read between the lines.)

  
With Raphael’s help things became rather… anti climatic. Not to say it wasn’t a hell of a fight (especially since Raphael had laud down the condition of not killing those who were simply protecting the clan rather than Camille’s loyalists.) But between the six of them (Simon had insisted on coming along despite protests from all but Magnus. He could handle a blade and surprisingly Alexander’s worries about Clary wasting time protecting him had zero merit as Raphael of all people seemed to make himself Simons personal shield) the work was done with minimal injury.

By the end Camille was nothing but dust . Now Magnus never considered himself a vengeful person but seeing Simons eyes lighten at that news made his feel a sadistic sting of pleasure. He hoped it had been painful.

  
Raphael had a brief talk with Clary before giving them all a curt nod and announcing Spain was pleasant this time of year before walking off, Magnus feeling that nagging feeling that they’d see the vampire again. He was no oracle but he had learned to trust his gut if nothing else.

  
They were all meeting at Clary’s for a ‘we’re alive!’ celebration. Magnus was headed out to meet them there when a strong hand on his shoulder pulling him back as the others drove off.

  
He turned to see Alexander, looking flustered but not from the fight, a sort of determination in his eyes “I don’t- I can’t-“ he made a noise of frustration before pulling Magnus into a kiss unlike the one they’d shared before. Where that one had been hesitant and brief this one was filled with passion and seemed to be never ending.

  
As he was backed up against the wall Magnus realized he had not even the faintest idea of how this would turn out for them.

  
And wasn’t that exciting?


End file.
